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Finding the Fourth Proportional to 137.40, 188.43 and 129.72

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Solution

The fourth proportional to 137.40, 188.43 and 129.72 is: 177.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.40 : 188.43 = 129.72 : x
  2. Step 2: Convert to fraction form
    137.40/188.43 = 129.72/x
  3. Step 3: Cross multiply
    137.40x = 188.43 × 129.72
  4. Step 4: Simplify right side
    137.40x = 24,443.14
  5. Step 5: Solve for x
    x = 24,443.14/137.40
  6. Step 6: Final answer
    x = 177.90

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.